I believe there have been studies showing estimation of durations
influenced by metabolic rate--at high  rate, time seems to pass more
slowly, etc.--but cannot cite them.  Possibly there is an explanation
along these lines.  Metabolic rate itself not likely to change within a
brief period of a traumatic event, but some correlates of (and/or
signals for?) an increased rate might be elicited.  Catecholamines
and/or excitatory amino acids??

Might be fruitful to look into endogenous clocks/pacesetters:
suprachiasmatic nucleus, others?    Beginning to free-asociate in wsee
hours of morning...seems to me at least one paper at International
Neuropsychological Society meeting in Boston (early Feb.) might be
relevant...further installment on previously-reported patients with
suprachiasmatic lesion...not only circadian but also much shorter term
timing off?   There is lit on different parts of brain being relevant
for different orders of magnitude of "timing"...

All I can do this hour of morning, but may suggest ideas others can
develop better.

F. Frank LeFever, Ph.D.
New York Neuropsychology Group

I was walking cautiously along the top of a cliff in winter, with the
rocks frosted over. In fact the frost was concealing some
ice. Suddenly my feet shot from under me towards the cliff edge. I
twisted my head to see the ground coming up, studied it carefully all
the way to the cliff edge, worked out the first place I could try to
get finger purchase on, and two later places I could reach for if I
slipped off the first. In identifying these three places I rejected
about twice as many as no good, decided I'd have no time to try for
more than three, and worked out exactly how to orient my hands to get
the best grip on each. I had to do this in advance because once I hit
the ground I might have to move very fast.  I rammed my fingers onto
the first, slipped off, grabbed for the second, and fortunately
stopped dead. Including reaction time I must have done all that within
0.5 sec. When I looked up one of my companions was beginning to look
horrified, and the other one (in front) was starting to turn round.

Normally that kind of thinking would take me a few seconds, rather
than less then 0.5 secs.

I have corresponded with motorcyclists and rock climbers who've had
similar experiences. Our consensus was that it was definitely a real
speed-up -- one is able to think and perceive around five to ten times
as fast as normal. It's utility is that it allows one to plan a
possibly life-saving complicated physical manoeuvre in a
life-threatening situation in a very short space of time. If it has
happened to you once, it has probably happened many times, i.e., some
people seem to be prone to it. It doesn't always happen, for no
reasons we could decide on.

I have no idea how anyone could gather the data necessary to decide
that this is a "chemical reaction". I suspect that is a "deduction"
along the dumb lines of "what else could it be?" If you can't think of
two other things it could be in less than one second you're not
thinking fast enough :-)
--

School of Artificial Intelligence,     Division of Informatics  
Edinburgh University,   5 Forrest Hill, Edinburgh, EH1 2QL, UK
<http://www.dai.ed.ac.uk/daidb/people/homes/cam/>     DoD #205